Age: In gestation.
Appearance: Like the wind.
In what way? As the fourth generation (geddit?) of high-speed mobile internet, 4G is a) invisible, and b) very fast.
How fast? About 10 megabits per second.
Which means what? That it's about 10 times quicker than 3G, the wireless system currently used by smartphones.
And how will this change my life? You'll be able to watch The X Factor, in high-definition, on your phone!
Is that it? You could play multiplayer Grand Theft Auto, on your phone!
Right. Anything else? You could video-call your mum! On your phone!
I'm sold. When can I get it? In fact, forget 4G: when I get some decent phone reception full-stop? Where do you live?
Rural Yorkshire. Ah. I'm afraid 4G is currently only being trialled in central London and Canary Wharf.
You mean a bunch of bankers can use their smartphones to play multi-player Modern Warfare 3 while I abseil from my bathroom trying to find a single bar of reception? In theory. Except that since no phone is yet 4G-compatible, the 1,000 anointed triallists will only be able to access the network on their tablets and laptops, with the help of some handy dongles.
How do you become a triallist? By being a lucky O2 customer, or working for John Lewis.
I must say this is bloody unfair. I work at Debenhams, and I'm with Vodafone. In which case you'll have to be patient.
Why? Because a) due to complex bandwidth constraints, 4G can't be rolled out nationally until 2013, when our TV networks switch from analogue to digital.
And b)? Mobile companies are still squabbling about how much they should pay to use the bandwidth.
How are other countries managing? Slightly better. 4G is already fully operational in parts of the US, and has been used by laptop owners in Germany and Scandinavia.
Do say: "Yes I know you're on the train – it's a video call."
Don't say: "I SAID I'M ON THE TRAIN!"
